Magnetic storage arrangements in which information is represented in terms of single wall domains such as magnetic bubbles are well known. When a number of bubble channels are defined in a single layer of material by a pattern of magnetic elements which cause the movement of bubbles in response to a magnetic drive field reorienting (i.e., rotating) in the plane of the layer, the arrangement is termed a "field-access" arrangement.
U.S. Pat. No. 3,618,054 of P. I. Bonyhard, U. F. Gianola and A. J. Perneski, issued Nov. 2, 1971 discloses a "major-minor" organization for field-access, bubble memories. The channels in such an organization are defined as loops in which bubble patterns are recirculated as the drive field rotates. These loops are permanent stores and are called the minor loops. A single accessing channel is employed to move information from the minor loops to a write and read port for manipulation. This accessing channel is called the "major loop" if defined as a recirculating channel and is called a "major path" if information is not returned by the path to the originating minor loop. Information is usually transferred to and later returned from the major loop if a major loop is employed. If a major path is employed, bubble movement between the minor loops and the major path typically is accomplished by replication followed by annihilation of the replicated information. Transfer, annihilation, and replication implementations are known in the art.
It is also known to employ oscillators to generate tones of the type employed, for example, in TOUCH-TONE telephone handsets. The tones are usually generated in pairs, one-out-of-four low frequency tones and one-out-of-three high frequency tones corresponding to a three by four pushbutton array familiar to telephone subscribers.